"About 72 women are diagnosed every day, that’s about 25,000 a year. The good news, though, is that four out of five will survive," says Dr. Blair Bigham. (Sarbinaz/Shutterstock)

The group that exercised more vigorously than the other, Bigham said, showed much greater brain function because of it.

"What they found is that 15 minutes of extra vigorous exercise a day, compared to about four to five [minutes] in the other group, was very very helpful at reducing the cognitive problems that come after treatment," Bigham said.

"That doesn't seem like a lot, but if you're not focused on that, if you don't have the intention of doing that everyday, I can see how it would fall by the wayside in their very very busy lives."

Doctors need to focus on recovery as well, Bigham says

While the study helps show that exercise helps in relieving the brain fog caused by cancer, doctors need to play a greater role in the recovery stage, Bigham said.